scholarly journals Susceptible supply limits the role of climate in the COVID-19 pandemic

Author(s):  
Rachel E. Baker ◽  
Wenchang Yang ◽  
Gabriel A. Vecchi ◽  
C. Jessica E. Metcalf ◽  
Bryan T. Grenfell

AbstractPreliminary evidence suggests that climate may modulate the transmission of SARS-CoV-2. Yet it remains unclear whether seasonal and geographic variations in climate can substantially alter the pandemic trajectory, given high susceptibility is a core driver. Here, we use a climate-dependent epidemic model to simulate the SARS-CoV-2 pandemic probing different scenarios of climate-dependence based on known coronavirus biology. We find that while variations in humidity may be important for endemic infections, during the pandemic stage of an emerging pathogen such as SARS-CoV-2 climate may drive only modest changes to pandemic size and duration. Our results suggest that, in the absence of effective control measures, significant cases in the coming months are likely to occur in more humid (warmer) climates, irrespective of the climate-dependence of transmission and that summer temperatures will not substantially limit pandemic growth.

Science ◽  
2020 ◽  
pp. eabc2535 ◽  
Author(s):  
Rachel E. Baker ◽  
Wenchang Yang ◽  
Gabriel A. Vecchi ◽  
C. Jessica E. Metcalf ◽  
Bryan T. Grenfell

Preliminary evidence suggests that climate may modulate the transmission of SARS-CoV-2. Yet it remains unclear whether seasonal and geographic variations in climate can substantially alter the pandemic trajectory, given high susceptibility is a core driver. Here, we use a climate-dependent epidemic model to simulate the SARS-CoV-2 pandemic probing different scenarios based on known coronavirus biology. We find that while variations in weather may be important for endemic infections, during the pandemic stage of an emerging pathogen the climate drives only modest changes to pandemic size. A preliminary analysis of non-pharmaceutical control measures indicates that they may moderate the pandemic-climate interaction via susceptible depletion. Our findings suggest, without effective control measures, strong outbreaks are likely in more humid climates and summer weather will not substantially limit pandemic growth.


PEDIATRICS ◽  
1967 ◽  
Vol 40 (4) ◽  
pp. 669-684
Author(s):  
Wallace A. Clyde ◽  
Floyd W. Denny

Mycoplasmas compose a ubiquitous group of minute microorganisms which include saprophytes, commensals, and pathogens. Of the seven species which have been isolated from man, only Mycoplasma pneumoniae has clearly established pathogenicity. Research continues to seek other possible disease relationships, since there are various animal diseases caused by mycoplasmas which have counterparts among human illnesses of unknown cause. M. pneumoniae can be associated with a wide spectrum of respiratory tract disease, including bullous myringitis, pharyngitis, tracheobronchitis, pneumonia, and subclinical infections. These illnesses are generally mild and occur most frequently between ages 5 and 19 years in slowly progressive epidemics. The clinical aspects of the disease are indistinguishable from virus-associated syndromes, and epidemiologic features are often more suggestive of the diagnosis. Techniques for M. pneumoniae cultivation and serodiagnosis are now adaptable for use in clinical laboratories. Non-specific diagnostic tests, especially cold hemagglutination, have distinctly limited usefulness in pediatrics. M. pneumoniae is sensitive to the tetracycline drugs and erythromycin; administration of these antibiotics shortens the clinical course of disease but may not be effective for prophylaxis or elimination of the carrier state. For these reasons, vaccines could provide more effective control and are being developed; however, greater experience concerning the relative role of M. pneumoniae among other respiratory disease agents is required before the need for control measures in the general population can be assessed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giovanni Franzo ◽  
Matteo Legnardi ◽  
Laura Grassi ◽  
Giorgia Dotto ◽  
Michele Drigo ◽  
...  

AbstractAleutian mink disease virus (AMDV) is one the most relevant pathogens of domestic mink, where it can cause significant economic losses, and wild species, which are considered a threat to mink farms. Despite their relevance, many aspects of the origin, evolution, and geographic and host spreading patterns of AMDV have never been investigated on a global scale using a comprehensive biostatistical approach. The present study, benefitting from a large dataset of sequences collected worldwide and several phylodynamic-based approaches, demonstrates the ancient origin of AMDV and its broad, unconstrained circulation from the initial intercontinental spread to the massive among-country circulation, especially within Europe, combined with local persistence and evolution. Clear expansion of the viral population size occurred over time until more effective control measures started to be applied. The role of frequent changes in epidemiological niches, including different hosts, in driving the high nucleotide and amino acid evolutionary rates was also explored by comparing the strengths of selective pressures acting on different populations. The obtained results suggest that the viral passage among locations and between wild and domesticated animals poses a double threat to farm profitability and animal welfare and health, which is particularly relevant for endangered species. Therefore, further efforts must be made to limit viral circulation and to refine our knowledge of factors enhancing AMDV spread, particularly at the wild-domestic interface.


mSphere ◽  
2018 ◽  
Vol 3 (5) ◽  
Author(s):  
Alison M. Day ◽  
Megan M. McNiff ◽  
Alessandra da Silva Dantas ◽  
Neil A. R. Gow ◽  
Janet Quinn

ABSTRACTCandida aurishas recently emerged as an important, multidrug-resistant fungal pathogen of humans. Comparative studies indicate that despite high levels of genetic divergence,C. aurisis as virulent as the most pathogenic member of the genus,Candida albicans. However, key virulence attributes ofC. albicans, such as morphogenetic switching, are not utilized byC. auris, indicating that this emerging pathogen employs alternative strategies to infect and colonize the host. An important trait required for the pathogenicity of many fungal pathogens is the ability to adapt to host-imposed stresses encountered during infection. Here, we investigated the relative resistance ofC. aurisand other pathogenicCandidaspecies to physiologically relevant stresses and explored the role of the evolutionarily conserved Hog1 stress-activated protein kinase (SAPK) in promoting stress resistance and virulence. In comparison toC. albicans,C. aurisis relatively resistant to hydrogen peroxide, cationic stress, and cell-wall-damaging agents. However, in contrast to otherCandidaspecies examined,C. auris was unable to grow in an anaerobic environment and was acutely sensitive to organic oxidative-stress-inducing agents. An analysis ofC. aurishog1Δ cells revealed multiple roles for this SAPK in stress resistance, cell morphology, aggregation, and virulence. These data demonstrate thatC. aurishas a unique stress resistance profile compared to those of other pathogenicCandidaspecies and that the Hog1 SAPK has pleiotropic roles that promote the virulence of this emerging pathogen.IMPORTANCEThe rapid global emergence and resistance ofCandidaauristo current antifungal drugs highlight the importance of understanding the virulence traits exploited by this human fungal pathogen to cause disease. Here, we characterize the stress resistance profile ofC. aurisand the role of the Hog1 stress-activated protein kinase (SAPK) in stress resistance and virulence. Our findings thatC. aurisis acutely sensitive to certain stresses may facilitate control measures to prevent persistent colonization in hospital settings. Furthermore, our observation that the Hog1 SAPK promotesC. aurisvirulence akin to that reported for many other pathogenic fungi indicates that antifungals targeting Hog1 signaling would be broad acting and effective, even on emerging drug-resistant pathogens.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
J. J. Luna-Guevara ◽  
M. M. P. Arenas-Hernandez ◽  
C. Martínez de la Peña ◽  
Juan L. Silva ◽  
M. L. Luna-Guevara

Many raw vegetables, such as tomato, chili, onion, lettuce, arugula, spinach, and cilantro, are incorporated into fresh dishes including ready-to-eat salads and sauces. The consumption of these foods confers a high nutritional value to the human diet. However, the number of foodborne outbreaks associated with fresh produce has been increasing, with Escherichia coli being the most common pathogen associated with them. In humans, pathogenic E. coli strains cause diarrhea, hemorrhagic colitis, hemolytic uremic syndrome, and other indications. Vegetables can be contaminated with E. coli at any point from pre- to postharvest. This bacterium is able to survive in many environmental conditions due to a variety of mechanisms, such as adhesion to surfaces and internalization in fresh products, thereby limiting the usefulness of conventional processing and chemical sanitizing methods used by the food industry. The aim of this review is to provide a general description of the behavior and importance of pathogenic E. coli in ready-to-eat vegetable dishes. This information can contribute to the development of effective control measures for enhancing food safety.


Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1623
Author(s):  
Salvatore Moricca ◽  
Tiziana Panzavolta

Tree pathogens and pests are fundamental components of forest ecosystems. By killing and decomposing susceptible trees, they regulate the cycle of nutrients and energy flow, thus shaping the structure and composition of forest stands. However, ecosystems can be seriously disrupted when the population density of these parasites increases beyond their tolerance level. Ascertaining the origin of pathogen and pest outbreaks, recognizing their causal agents in a precise and unequivocal way, while understanding their reproductive and dispersive dynamics are all crucial for the implementation of effective control measures. The studies collected in this special issue cover a wide range of topics in the field of forest pathology and entomology. Investigations range from molecular diagnosis of pathogens and pests to their monitoring and quantification in the field, from measurements of their proliferation rate to the analysis of their genetic variability, from the assessment of the role of plant diversity and ecosystem heterogeneity on pathogen and pest impacts to disease and pest management. Specific case studies show how applied research conducted with innovative methods is key to solving taxonomic issues that were, until now, controversial. The variety of experimental approaches and the range of scientific issues addressed document the trends and topicality of modern forest health protection science.


2020 ◽  
Author(s):  
Lukman Olagoke ◽  
Ahmet E. Topcu

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable


2021 ◽  
Vol 13 (1) ◽  
pp. 408
Author(s):  
Fernando Almeida-García ◽  
Rafael Cortés-Macías ◽  
Krzysztof Parzych

This study analyzes the role of residents in urban tourist destinations affected by the increase in tourist flows, which have generated various problems such as tourism, gentrification and the emergence of tourism as a threat to residents. The role of residents in tourist destinations has not been analyzed regularly during the development process of destinations. We study two cases of historic centers in European cities, with the aim of comparing tourism problems, which are common to most European urban destinations. This study was conducted by administering surveys amongst residents of these historic centers (378 in Málaga, Spain, and 380 in Gdansk, Poland). These cities show a similar demographic size and urban characteristics. This is the first comparative research on tourism-phobia and gentrification in destinations, a field of analysis that is still not studied much. We develop specific scales to measure gentrification and tourism-phobia; moreover, we study the impact of some tourist problems that affect residents (noise, dirt, occupation of public spaces, etc.), and we show the spatial distribution of tourism-phobia. The same analysis instruments are used for both cities. The results of this study show that the tourism-phobia situation is different in the analyzed destinations. It is more intense in the case of Málaga than in Gdansk. The two historic centers are especially affected by the processes of increased tourist flows and the growth of new forms of tourist accommodation. The research results show that the residents’ annoyance caused by tourism gentrification is more intense than tourism-phobia. Both case studies highlight the residents’ complaints regarding the inadequate management of problems by public stakeholders and control measures.


Author(s):  
Ting Wan Tan ◽  
Han Ling Tan ◽  
Man Na Chang ◽  
Wen Shu Lin ◽  
Chih Ming Chang

(1) Background: The implementation of effective control measures in a timely fashion is crucial to control the epidemic outbreak of COVID-19. In this study, we aimed to analyze the control measures implemented during the COVID-19 outbreak, as well as evaluating the responses and outcomes at different phases for epidemic control in Taiwan. (2) Methods: This case study reviewed responses to COVID-19 and the effectiveness of a range of control measures implemented for epidemic control in Taiwan and assessed all laboratory-confirmed cases between 11 January until 20 December 2020, inclusive of these dates. The confirmation of COVID-19 infection was defined as the positive result of a reverse-transcriptase–polymerase-chain-reaction test taken from a nasopharyngeal swab. Test results were reported by the Taiwan Centers for Disease Control. The incidence rate, mortality rate, and testing rate were compiled, and the risk ratio was provided to gain insights into the effectiveness of prevention measures. (3) Results and Discussion: This study presents retrospective data on the COVID-19 incidence rate in Taiwan, combined with the vital preventive control measures, in a timeline of the early stage of the epidemic that occurred in Taiwan. The implementation of multiple strategy control measures and the assistance of technologies to control the COVID-19 epidemic in Taiwan led to a relatively slower trend in the outbreak compared to the neighboring countries. In Taiwan, 766 confirmed patients were included, comprised of 88.1% imported cases and 7.2% local transmission cases, within the studied period. The incidence rate of COVID-19 in Taiwan during the studied period was 32 per million people, with a mortality rate of 0.3 per million people. Our analysis showed a significantly raised incidence risk ratio in the countries of interest in comparison to Taiwan during the study period; in the range of 1.9 to 947.5. The outbreak was brought under control through epidemic policies and hospital strategies implemented by the Taiwan Government. (4) Conclusion: Taiwan’s preventive strategies resulted in a drastically lower risk for Taiwan nationals of contracting COVID-19 when new pharmaceutical drug or vaccines were not yet available. The preventive strategies employed by Taiwan could serve as a guide and reference for future epidemic control strategies.


2020 ◽  
Vol 13 (1) ◽  
pp. 238
Author(s):  
Alice Giusti ◽  
Enrica Ricci ◽  
Laura Gasperetti ◽  
Marta Galgani ◽  
Luca Polidori ◽  
...  

Proper investment in mushroom production (farming and wild mushroom picking activities) may represent a winning strategy for many countries, including Italy, to better face the problems of food security and environmental impact, and to break away from imports, enhancing the local products. However, the risk related to the consumption of poisoning species requires governments to implement or reinforce effective control measures to protect consumers. Mushroom identification by phenotype observation is hardly applicable if morphologically-similar species, non-whole specimens, or clinical samples are involved. Genotypic analysis is a valid alternative. An ongoing research project involving the Experimental Zooprophylactic Institute of Lazio and Tuscany, the regional Mycological Inspectorate, the Tuscany Mycological Groups Association, and the Department of Veterinary Sciences of the University of Pisa aims to reinforce the collaboration among institutions for the management of mushroom poisoning. The core’s project aims to develop an internal genetic database to support the identification of wild and cultivated mushroom species in the Italian territory. The database will include Internal Transcribed Spacer (ITS) sequences retrieved from official databases (the NCBI GenBank and the BOLD system) which are considered to be reliable, after a proper selection process, and sequences from specimens collected directly and identified by expert mycologists. Once it is validated, the database will be available and further implementable by the official network of national laboratories.


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